P2.0.6 Schottky Type Ag-TiO2 Hydrogen Sensor: Gas Sensing Mechanism and Modeling
- 14th International Meeting on Chemical Sensors - IMCS 2012
2012-05-20 - 2012-05-23
- P2.0 Metal Oxide-based Sensors
- S. Rahbarpour - Electrical Engineering Department, K. N. Toosi University of Technology (Iran), S. Hosseini-Golgoo - Electrical Engineering Department, Guilan University (Iran)
- 1275 - 1278
The use of Schottky type noble metal-metal oxide gas sensors is spreading due to their unique gas sensing properties. In this paper, hydrogen detection using Ag-TiO2-Ti diodes is reported. The I-V characteristics of these diodes are highly sensitive to the partial pressure of hydrogen contamination in the surrounding atmosphere. At the reducing atmosphere the energy barrier height established at the Ag-TiO2 junction reduces due to silver work function variation and the junction behaves as an ohmic
contact in a highly reducing atmosphere. This reversible transition from Schottky to ohmic behaviour was modelled qualitatively and quantitatively based on the hydrogen-silver interaction. The model was experimentally confirmed.